The present dissertation focuses on the use of verbal irony in conversation. The main goal is to outline the parameters for characterizing verbal irony as a prototype category. Two issues have motivated this research. The first is that most of the scholars have defined verbal irony as an Aristotelian category with necessary and sufficient conditions, even though many of them are aware that different instances of irony exist. Secondly, some of these definitions are based on the analysis of ironic sentence in isolation or in the context of constructed text. Therefore, these definitions fail to explain many instances of verbal irony in naturally occurring conversation.

Thus, I claim that verbal irony is a prototype category. The classical, Aristotelian theory of categorization states that categories are defined in terms of necessary and sufficient conditions that exhibit clear-cut boundaries and permit only two degrees of membership (i.e. member and non-member). On the other hand, the prototype view of categories considers that a prototype is a typical instance of a category and that other instances are assigned to the category on the basis of their similarity to the prototype. Thus, there are degrees of membership based on degrees of similarity: the closer an entity is to the prototype, the more central its status within the category. In other words, there are prototype members, which share the main attributes, and peripheral members, which share some of those attributes. Finally, I propose that an exploration of irony's attributes is most clearly revealed through the analysis of conversation because the conversation is the basic site of verbal irony.

To achieve the goal of the present research, I analyzed excerpts from ten face-to-face multiparty conversations in Argentinean Spanish. These conversations were audio-recorded and transcribed according to Conversational Analysis conventions. The subjects are my relatives and friends from the city of Santa Fe, Argentina. The benefit of the selected subject population is that they share contextual background, which is recognized as the main factor in the interpretation of an utterance as ironic.

My research shows empirically -through an ethnomethodological analysis of real conversations- that verbal irony is a prototype category. I found in the data compelling evidence for graded membership of this category. I found that the prototypic ironic instances or central members of the category present an opposition between the literal and the intended meaning of the utterance, a hidden attitude of criticism, a victim of the criticism, and shared experience and knowledge that help the audience infer the irony. I found that in the less-than-central members the opposition between what is said and what was said in previous utterances leads the audience to infer the irony. However, in the case of moderately marginal members the opposition between what the speaker says and the facts of the situation is what leads the audience to interpret the utterance as ironic. In the extreme marginal members, I did not find any kind of opposition. In these instances the ironic interpretation is triggered by the negation of the felicity conditions of a speech act, or from the echo of a previous utterance, as was described by Sperber and Wilson in their Mention Theory of irony. Finally, the identification of ironic instances in real conversations is sometimes complicated by the presence of sarcasm and parody because these three phenomena are closely related. Indeed, I found good representative examples of each of these categories as well as instances in which two of them overlap.